1. Field of the Invention
Embodiments of the invention relate to a semiconductor integrated circuit device and a related fabrication method. In particular, embodiments of the invention relate to a semiconductor integrated circuit device and a method for fabricating the manufacturing the semiconductor integrated circuit device in which contacts can be formed in a cell array region and a peripheral circuit region of a semiconductor substrate at the same time.
This application claims priority to Korean Patent Application No. 10-2006-0026265, filed on Mar. 22, 2006, the subject matter of which is hereby incorporated by reference in its entirety.
2. Description of Related Art
Self-aligned contacts formed in a cell array region of a semiconductor substrate have a different size, shape, and function than contacts formed in a peripheral circuit region and connected to a metal wire. In addition, self-aligned contacts formed in a cell array region are formed from a different type of conductive material than contacts formed in a peripheral circuit region and connected to a metal wire. Thus, contacts disposed in a cell array region of a semiconductor substrate and contacts disposed in a peripheral circuit region of a semiconductor substrate cannot be formed using a single process. In addition, as the design rule for semiconductor integrated circuit devices has been reduced, problems have arisen in the peripheral circuit region as well as the cell array region. Examples of such problems are difficulty acquiring the open margins required for the formation of contacts, increase in contact resistance resulting from the reduction in size of source/drain regions, and deterioration of the leakage current characteristic.
In addition, when polysilicon is used as a conductive material to form contacts in the peripheral circuit region on transistors that have different conductivities, processes for implanting different impurities should be performed. Thus, when forming those contacts in the peripheral circuit region, complicated processes for forming contacts (such as several photoresist processes) may need to be performed separately from the process for forming contacts in the cell array region.